Reflecting-lamp



H. A. DOUGLAS REFLECTING LAMP.

APPLICATION FILED NOV. 14, 1918.

1,339,695 Patented May 11,1920.

" TED srArs PATENT OFFICE.

HARRY A. DOUGLAS, 0]? BRONSON, M,.IGHIGAN, LASSIGNOR TO DOUGLAS 8; RUDD MFG.

, 70., OF BRONSON, MIGHIGAN,,A CORPORATION OF MICHIGAN.

REFLECTING-LAMP.

Specification of Letters Patent.

original application filed. December 5,1916, Serial No. 135,117. Divided and this application. filed November 14, 1918. Serial No. 262,488.

To all whom it may concern it known that l, HARRY A. DouoLAs, citizen of the United States, residin at Bronson, in the county of Branch and btate of Michi an, have invented a certain new and useiul Improvement in Reflecting- Lamps, of which the following is a full, clear, concise, and exact description.

M invention relates to reflecting lamps employing dish-shaped or concave casings and dish-shaped or concave reflectors surrounded thereby, the reflecting surfaces bcing usually parabolic, this application being a division of my original application Serial No. 135,117, filed December 5, 1916.

My invention has for one of its objects the provision or an improved assembly between the reflector and the casing therefor at the forward portions of these two elements of the lamp structure.

lhe invention has for another object the provision of an improved means for mounting the light transmitting closure that 18 provided at the forward end of the lamp structure.

My invention, in all of its aspects, will be pointed out in the claims and will be fully described in connection with the accompanying drawing showing the preferred embodiment of the invention and in which Figure 1 is a view in longitudinal sectional elevation; Fig. 9. is a view on line 2-2 of Fig. 1; Fig. 3 is a view showing the preferred formation of the central portion of the reflector shell; Fig. 4 is a top plan yieW of a part of the structure shown in Fig. l with a portion broken awa Fig. 5 is a view of an abutment which preierably enters into the construction; Fig. 6 shows a IIlOtllfiCittion of the structure illustrated at the lower portion of Fig: '1 and in Fig. 4:; Fig. 7 is 'bottom view of a part of the structure shown in Fig. 6 with a portion broken away; and. Fig. 8 is a perspective view of a part of the structure illustrated in Fig. 1 shown in unasseinbled relatieu- Like parts are indicated by similar charactersof reference throughout the different figures v The concave casing 1 and the concave rcilector shell. 2 that projects intothe casing are coupled at the forward end ofth'e lamp structure by means of my invention. The means by which the coupling between the elements 1 and Q o'f'the lamp is effected desirably include a plurality of bayonet catches 3 distributed around and carried by one of the elements, preferably the casing 1. In the construction shown in Figs. 1, 4c and 8, the bayonet catches 3 project through bayonet Slotsr provided in the rear continuation 5 of a retaining ring 7, preferably S-shaped in cross section, which operates to hold the casing and reflector shell together and which retaining ring is desirably completely curled over to form a hollow annular bead 8 that conceals the projecting ends of the bayonet catches. In this preferred construction the reflector is movable backwardly and for wardly with respect to the casing. The rcfiector shell 2 is desirably provided With a surrounding flange 9 integrally formed therewith and which flange is provided with an annular groove 10 that receives ing cord 11. The light trausmitting closure 12 is held against the packing cord 11' at the Patented May 11, 1920.

the packfront of the reflector by means of the annular edge of the unclosed front annular loop or bead 8 of the retaining ring 7. When it is desired to remove the closure 12 and to separate the casing and reflector, the retaining ring 7 is merely turned until the bayonet catches 3 are disengaged from the bayonet slots 4 to permit the retaining ring to be removed. In the construction shown in Figs. and 7 the bayonet catches 3 are provided upon the reflector shell arid engage bayonet slots 4 that are provided in the casing, this casing being backwardly curled as indicated at 1 to form a hollow bead that conceals the projecting ends of the bayonet catches. In the construction shown in Figs. 6 and 7, the light transmitting closure 12 is in front of and overlies the reflector shell and is permanently held between the packing cord 11 at the rear of the closure and the packing cord 13 at the front of the closure, this light reflectin shell 2 being inwardlycurled at 14 to hold the packing cord 13 in place. In the construction shown in Figs. 6 and 7 the reflector shell and easing are directly coupled by means of the bayonet catches 3 and the bayonet slots 4', but in the preferred construction of Figs. 1, 4:

and 8 the casing and-reflector shell are rret" glass 12 rtowardthe retai n I the ligating center.

- structure the tubular ing ring 7 whose front edge engages the front face of said cover; The retaining ring in turn couples the forward ends of the rel'lector shell and casing. Said retaining ring thus is a separable part of the casing and the reflector is movable with relation to the casing along the common axis 01 these two elements, wherclrvthe spring 18 is free to perform its function.

The circuit connector shell 15 is provided at its front and rear end with means'for attaching thereto circuit continuing devices,

a lam p bulb being receivable at the forward end of the connector shell 15 and a plug at the rear end of the connector shell. The connector shell 15 has a threaded formation thereupon as indicated at 16, the threads at 16 being desirably formedupon-an enlargement of'the shell which may be in the nature of a separately formed collar that is rigidly attachedto the connector shell to form an integral or fixed part thereof. The threads 16 upon the connector shell have threaded engagement with 'a sleeve 17 carried by the casing; This sleeve 17 is desirably tubular, the connector shell 15 passing through the bore accessible at the rear of the sleeve 17- for attachment thereto of a circuit continuing plug. Spacing intervenes between the forward end of the tubular adjusting sleeve 17 and the connector shell 15 for the reception of rear end of the compression spring 18 whose forward end bears against the rear end of the reflector shell 2 to press the same forwardly. The rear end of the reflector shell is provided with an opening 19 in which the forward end of the connector shell 15 may move longitudinally of the of the lamp the connector shell carrying a tongue 20 that enters the slot 21 formed in the connector shell 1-5 to prevent rotation of this connector shell 15. The tubular adjusting sleeve 17 has a flange 22 formed therein that engages the rear of the casing 1, the spring 18 maintaining the flange or enlargement 22 in engagement with the inner surface of the casing through the intermediation of the collar 16 and-the thread ed engagement of this collar 16 with the adjusting sleeve 17 that is movable longitudinally of the lamp axis. In. assembling the is slipped rearwardly through the opening; provided at the rear of the-casing, longitudinally of the lamp axis the flange 22 limiting the extent to which the sleeve 17' may be moved rearwar lly and to maintain the sleeve in a l'ixed plane of rotation and in assembly with the casing. When it is desired to adjiist or element 23 (which of the sleeve 17 to be adjusting sleeve 17 may be in the form of a' filament withint-he lampv bulb 24) the adjusting sleeve 17 is turned to the right or he according to the direction in which the lamp bulb is to be moved, and inasmuch as the connector shell 15 can not be turned owing to the engagement of the tongue 20 in the slot 21 in the shell 15, the shell 15 must be moved back-- ward or forward according to the direction of rotation of the'adjusting sleeve 17, the spring 18 operating at all times to maintain the flan e 22 in engagement with the casing l where y not only will the adjusting sleeve 17 be prevented from shifting its position longitudinally of the axis of the lamp portion, but whereby also the adjustment-of the lamp bulb effected by the rotation of the sleeve 17 will be maintained.

While I have herein shown and particularly described the preferred embodiment of my invention I do not wish to be limited to the precise details of constructionshown as changes may readily be made without departing from the splrit of my invention, but having thus described my invention I claim as new and desire to secure by Letters Patent the following l. A lamp structure includin a concave casing; a concave reflector shelfwithin the casing and movable backwardly and forwardly with respect thereto; a spring in tcrposcd between the rear ends of the cast ing and reflector shell for pressing the reflector shell forwardly; a light transmitting cover in front of and o zerlying the reflector shell; and a retaining rin carried by the casing and engaging the rent face of the light transmitting cover, said retaining ring being S-shaped in'cross section and havin the rear part thereof forming a hollow beef; said retaining ring and net catch and slot cealed by said bead.

2. A lamp structure including a concave casing; a concave reflector shell within the casing and movable backwardly and forwardly with respect thereto; a spring for pressing the reflector shell forwardly; a light transmitting. cover in front of and overlying the reflector shell; and a retaim ing ring carried by the casing and engaging the front face of the light transmitting cover said retaining ring being S-shaped in cross sectionand having the rear part thereof casing having bayo- .forming a hollow head, said retainin ring HARRY a. DOUGLAS.

engagement at and con- 

